Identification of a novel role for Drosophila MESR 4 in lipid metabolism

Drosophila provides a powerful genetic model to analyze lipid metabolism. Drosophila has an adipose‐like organ called the fat body, which plays a crucial role in energy homeostasis. Here, we conducted a fat body‐specific misexpression screen to identify genes involved in lipid metabolism. We found that over‐expression of a nuclear protein with nine C 2 H 2 type zinc‐finger motifs and a PHD ‐finger, Misexpression suppressor of ras 4 ( MESR 4), reduces lipid accumulation in the fat body, whereas MESR 4 knockdown increases it. We further show that MESR 4 up‐regulates the expression of major lipases, which may account for the reduction in lipid storage in the fat body and the release of free fatty acids ( FFA s) in the body. These results suggest that MESR 4 acts as an important upstream regulator of energy homeostasis.